Electric connector for connecting two conductors through a wall



Dec. 29, 1959 2,919,421

H. J. MODREY ELECTRIC CONNECTOR FOR CONNECTING TWO CONDUCTORS THROUGH AWALL Filed Feb. 9, 1956 INVENTOR.

HENRY J. MODREY Maud/W ATTORNEY United States Patent ELECTRIC CONNECTORFOR CONNECTING TWO CONDUCTORS THROUGH A WALL Henry J. Modrey, Stamford,Conn. Application February 9, 1956, Serial No. 564,438 Claims. (Cl.339-59) This invention relates to electric connectors having a plugmember and a jack member, and more particularly to electric connectorsof this kind for connecting two conductors through a wall for example apanel or a bulkhead.

Connections through a wall frequently require that the connector sealsthe wall opening through which it extends. It is further often essentialthat the connection can be rapidly and readily established or separated,that it has satisfactory and substantially constant electric propertiesand that it is vibration proof.

Accordingly, one of the objects of the present invention is to provide anovel and improved electric connector of the kind above referred to, oneof the members of which, generally the plug, can be fastened in andsealed to the panel or wall by simply turning one of the components ofthe plug in one direction and equally conveniently released by turningthe said component in the opposite direction.

Another object of the invention is to provide a connector member whichcan be fastened in and sealed to the panel or wall without requiringspecial anchoring means or openings in the wall. In other words, aconnector member according to the invention can be fitted in anysuitably dimensioned aperture of the panel or wall thereby greatlysimplifying the mounting of the connector and reducingthe costs of both,manufacture and installation.

Still another object of the invention is to provide a connector memberwhich incorporates as a component an elastic axially deformable sleeveperforming the triple function of fastening, sealing and vibrationproofing the member.

Another object of the invention, allied with the preceding ones, is toprovide a novel and improved shielded or coaxial bulkhead or panelconnector which can be readily and conveniently detachably fastened inand sealed to a bulkhead or panel and which includes novel meansautomatically establishing a ground connection when the jack and theplug of the connector are applied to each other.

Yet another object of the invention is to provide a novel and improvedconnector design which requires a small number of parts, can beinexpensively manufactured by massproduction methods and be rapidly andconveniently assembled and installed.

While the device according to the invention is primarily designed foruse as an electric connector, certain features of the design-make thesame also advantageous for use as a quick-release mechanical fastener.

Other and further objects, features and advantages of the invention willbe pointed out hereinfater and set forth in the appendedclaims formingpart of the application.

In the accompanying drawing several preferred embodiments of theinvention are shown by way of illustration and not by way of limitation.

In the drawing: Fig. 1 is a side view, partly in section, of an electricconnector according to the invention, the jack and the plug of theconnector being shown separated from each other.

Fig. 2 is an exploded view of the components of the plug.

Fig. 3 is a sectional side view of a shileded or coaxial bulkhead orpanel connector according to the invention, the jack and the plug of theconnector being shown separated from each other.

Fig. 4 is an exploded view of the plug of the connector according toFig. 3.

Fig. 5 is a diagrammatic view of the installation of a car radioemploying the connector of Fig. l as current connector and the connectorof Fig. 3 as connector for the aerial.

Fig. 6 is a side view of a modification of the connector employed asmechanical fastener.

Fig. 7 is an exploded view of Fig. 6, and

Fig. 8 is a diagrammatic view of an assembly gun for assembling aconnector according to the invention.

Referring first to Figs. 1 and 2 in detail, the connector according tothese figures comprises a jack 1 and a plug 2. The connector, or morespecifically the jack thereof is designed to be fastened in and sealedto a wall 6 which for this purpose is provided with a suitablydimensioned opening 4. Wall 3 may be visualized as a metal panel orbulkhead.

As can best be seen in Fig. 2 the jack comprises an operating stud 5, acam member 6, an elastic axially deformable sleeve 7, a washer 8 and ahead nut 9.

Operating stud 5 comprises a stem 10 from one end of which a protrusion,preferably a two-sided protrusion 11 extends. The protrusion may beformed by a pin which extends through a transverse bore of the stem andis either fixedly or removably seated in the bore. However, for smalldimensions and also for reasons of mass production and mass installationthe stud design as shown in some of the figures of the presentapplication is preferable. As appears from Fig. 2 and the magnifiedinsert associated with the showing of the stud, protrusions 11 areproduced by pinching two wings out of the stud material. The hollows orindentations left by the gripping of the material during the pinchingoperation are clearly indicated in the insert at 11'. The stud isdrilled axially after the pinching operation, or it may be formedoriginally from tube stock. The end of the stud opposite protrusions 11is longitudinally knurled at 12. As is apparent, the stud is a one-piecedesign.

It has been found that a stud as shown herein can be convenientlymanufactured for very small dimensions of the connectors down to aboutinch diameter of sleeve 7 and has yet sufficient strength to withstandthe rather substantial axial pressure of about 60 lbs. exerted by thesleeve as will be more fully explained hereinafter.

Cam 6 is slidably and rotatably fitted upon the stud. It has on one enda fiat face intended for abutment against the respective face of sleeve7. The other side of the cam member is formed with two camming surfaces13 and 14 respectively, each occupying slightly less than of theperiphery. The peak of each camming surface is preferably indented toform rest notches 15 and 16 respectively.

The cam may be made of any generally metal or molded plastic.

Sleeve 7 is cylindrical and may be made of any material capable ofoutwardly bulging in response to an axial pressure and of substantiallyregaining its initial configuration upon relaxation of the axialpressure. Materials suitable for the purpose are various types ofnatural and synthetic rubber, rubber compositions or plastics. It isessential for the sleeve material to possess a high co-eflicient offriction in contact with surfaces made from metal, plastic or the like.

suitable rigid material,

The length of the sleeve is critical for the operation of the socket andthe considerations governing the length of the sleeve will be more fullydiscussed hereinafter.

Washer 8 is made of insulation material. To serve its purpose in thestructure in which it is used, the washer material must have a highfriction surface. It may be made of any material satisfying thisrequirement, for instance a suitable rubber or rubber composition orcoarse fiber.

Head nut 9 has a central bore 17 dimensioned to fasten the head with aforce fit upon the knurled portion 12 of stud 5. To facilitate turningof head 9 when fitted upon stud 5 for a purpose which will be more fullyexplained hereinafter, wings 18 are preferably provided.

The jack as hereinbefore described, is assembled by first slipping cam 6upon stud 5 so that wings 11 will ride on carnming surfaces 13 and 14.Then, sleeve 7 and washer 8 are successively slipped upon stud 5.Finally, head 9 is mounted by forcing it upon the knurled stud portion12.

One of the conductors to be connected by the connector is attached tothe jack by any suitable means. There is shown an insulated conductor 19ending in a closed lug 20. The lug is fitted upon the stud prior to theattachment of head 9. it is of course also possible to employ a lug ofthe spade type in which event the lug may be laterally slipped upon thestud, or the conductor end may be simply clamped between washer 8 andhead 9.

As is apparent from the previous description and Fig. l, turning of stud5 relative to cam 6 after assembly of the jack will cause an axialdisplacement of the cam on the stud within limits controlled by the riseof the camming surfaces thereby correspondingly varying the axial spaceavailable for sleeve 7 between washer 8 and the flat face of cam 6. Theaxial length of the sleeve is such that the length of the sleeve in itsfully relaxed condition is somewhat in excess of the available spacewhen wings 11 occupy the base of the carnming surfaces, or in otherwords when the space available for the sleeve is at a maximum. Thisposition of the cam constitutes the unlocked position of the plug. Dueto the aforedescribed excess length of the sleeve the same is slightlyaxially compressed and shows a slight outward bulging.

The jack assembly as hereinbefore described, is now ready for insertionin metal panel 3, the diameter of opening 4 and the maximum diameter ofsleeve 7 being correlated to permit passage of the slightly bulgingsleeve through opening 4. Rubber washer 3 when resting on panel 3 asshown in Fig. 1, insulates head 9 and conductor 19 from panel 3, thethickness of the washer controlling thte dielectric resistance of theconnector plug toward the panel.

To turn the jack from the described unlocked position into the lockedposition of Fig. 1, wings 11 must be turned from the position occupyingthe base of the respective camming surfaces into the upper position inwhich they occupy indentations 15 and 16 respectively. In other words,stud 5 must be rotated relative to cam member 6. The aforedescribedprecompression or preloading of sleeve 7 produces sufficient frictionbetween the faces of the sleeve and the adjacent sides of cam member 6and washer 3 respectively to permit rotation of stud 5 when the assemblyincluding cam member 6, sleeve 7 and washer 8 is held stationary. Thisis effected by pressing head 9 toward the panel simultaneously with theturning of the head. The aforedescribed comparatively high friction ofthe surface of washer 8 abutting against the panel will then supply therequired starting friction without the necessity of anchoring any partof the jack to the panel by special anchoring means such as hooksextending from the jack and engaging a corresponding hole in the panel.

As the wings ride along on the camming surfaces, the friction betweenthe engaging surfaces of the assembly within which stud 5 turns israpidly increased so that the components of the assembly remainstationary relative to each other and to the panel. At the same time,the loading of the sleeve and with it the outward bulging thereof areincreasing until finally sleeve 7 assumes the strongly outwardly bulgedshape shown in Fig. 1. As is evident, the bulging of the sleeve whichnow considerably overhangs the peripheral outline of opening 4 locks thejack tightly and moisture proof within the panel. To unlock the plug,stud 5 is simply turned in the opposite direction so that wings 11return into the position permitting reexpansion of the sleeve into itsinitial slightly bulged shape.

The properties of the rubber material used for the sleeve require thatthe sleeve is not axially compressed beyond a definite maximumcompression to prevent a permanent set of the sleeve material. Thecamming arrangement employed by the invention affords the advantage thatit positively limits the maximum axial compression of the sleeve to adesired value.

The plug part of the connector is shown as a single contact pin 21 whichis simply pushed into the hollow stud 5 which thus forms the receiverelement of the connector. Pin 21 is suitably secured to the secondconductor 22. The pin may be fastened to an insulated bracket or holderin such a manner that upon fitting the plug through the panel, thehollow stud 5 slides over the fixed pin 21 which in this design forms astationary outlet.

Figs. 3 and 4 show a modified connector design using the same principleas described in connection with Figs. 1 and 2. The connector of Figs. 3and 4 is particularly suitable for use as a shielded or co-axialbulkhead connector but it can also be used for connecting ordinaryconductors.

A shielded connector must connect the core conductors and should alsoestablish unbroken ground continuity completely surrounding theconductor core.

The connector of Figs. 3 and 4 again comprises a jack part 25 and a plugpart 26, the jack part being shown in Fig. 4 in an exploded view.

Cam member 6' is identical in shape with the cam member 6 used in thesocket of Figs. 1 and 2, but preferably made of nylon. Nut 9 is similarto nut 9 but formed with a sleeve opening 9" for extending the end of acoaxial cable through the nut. Stud 5 is similar to the stud 5 of Fig. 1except that the inner diameter of the stud part opposite to wings 11 ispreferably reduced at 27 to receive the inner core conductor 28 of acoaxial cable 29. The outer conductor of the cable, which is ofconventional design, is formed by metal braiding 29 insulated from coreconductor 28 by insulation material 39. Core wire 28 is secured to stud5 by crimping or soldering it in the narrow bore 27 of the stud as canbest be seen in Fig. 3. The sleeve 7 of the socket is formed with aflange or collar 31 instead of the separate washer 8. The outer wall ofthe sleeve and part of flange 31 are covered with a metalized layer 32to the extent shown in Fig. 3. The metallized coating must havesufficient flexibility to permit expansion of the sleeve from itsslightly bulged shape shown in Fig. 3 into its strongly bulged shapewhen the plug is locked as shown in Fig. 1 and described in connectiontherewith. A metal coating of sufficient flexibility may be obtained byspraying the rubber sleeve with a metallic deposit, or gluing a slashedmetal foil skirt onto the sleeve.

The contact between metal braid 29 and nut 9 is generally sufiicient forgrounding purposes. However, if a stronger mechanical attachment of thecoaxial cable to the plug is desired, the nut may be pressed upon themetal braid 29 by a simple pressing operation, or may be solderedthereto. Nut 9' and with it metal braid 29 are insulated from coreconductor 28 by an insulation sleeve 33 fitted in a corresponding boreof the unit. This sleeve may consist of a nylon insert.

The assembly of the jack is apparent from the previous description. Fig.3 shows the jack in its assembled and unlocked condition. The jack islocked by turning stud 5' into the position in which wings 11 occupy theindentations 15 and 16 at the upper end of the camming surfaces therebyforcing the rubber sleeve in the strongly bulged position indicated indotted lines. The necessary starting friction is again supplied by thepreloading of the sleeve and the frictional engagement between collar 31and panel or bulkhead 3. As can be clearly seen in Fig. 3, braiding 29is electrically connected to panel or bulkhead 3 through nut 9 and themetal coating 32 on sleeve 7. Panel or bulkhead 3 should be visualizedas being grounded.

The plug part 26 of the connector is shown as being assembled on aninsulation base plate 35 formed with mounting holes 36 and severalcircum-ferentially spaced slots 37 for the passage of fingers 38. Thefingers are joined below plate 35 to form a crimping sleeve 38' throughwhich is extended the second coaxial wire or cable to be connected. Thiscable consists of an outer metal braiding 39 and an inner or coreconductor 40 insulated from the braiding by insulation material 41. Thecoaxial cable is suitably secured within sleeve portion 38, for instanceby crimping the sleeve portion. The core conductor is inserted within ahollow contact pin 42 mounted within a further bore through base plate35.

Let it be assumed that it is desired to connect the two coaxial cablesthrough panel 3. For this purpose, the jack 25 is pushed togetherthrough the hole in the panel onto the stationary plug 26-. Contact pin42 will then enter stud 5' thereby connecting core conductor 28 withcore conductor 40 through stud 5'. Fingers 38 will frictionally engagethe metallized coating 32 of bulging sleeve 7'. To accommodate thebulging of the sleeve, fingers 38 are preferably outwardly bulged at38".

As is apparent, the engagement of fingers 38 with metal coating 32establishes a direct connection of metal braid 39 with metal braid 29and also with panel or bulkhead 3.

The connectors heretofore described serve as leadthrough connectorswhich seal and moisture proof the opening in which the plug part 25 ofthe connector is fitted.

The strongly expanding rubber sleeve used in both connector designsheretofore described renders the connectors capable of performing asecond function, to wit, to fasten two components to each other.

Fig. 5 shows a device 40 which may be visualized as a conventional carradio to be mounted on two brackets 49 and 49. The depending arm of eachbracket has an opening 43 corresponding to opening 4 in panel 3. Opening43 is aligned with an opening 44 of similar diameter through the sidewall of the casing of the radio. The left side of Fig. 5 shows astationary plug of the type illustrated in Fig. 3, but used to connect aonewire conductor rather than a coaxial cable. This plug when insertedin openings 43 and 44 and locked as previously described, secures theradio casing to bracket 49. At the same time the stud of the jack entersa plug 45 thereby connecting a wire 46 to the plug wire which may bevisualized as leading to the source of current for the radio. Plug 45 issecured to the casing of the radio by any suitable means such as abracket 47. A rubber washer 48 is preferably interposed between thebracketsand the radio casing. This washer is likewise held by theconnector and serves a vibration insulator.

The right hand side of Fig. 5 shows a jack 25 as described in connectionwith Figs. 3 and 4 used to connect coaxial cables. The jack may bevisualized as establishing the connection with the aerial for the radioand serves the additional purpose of securing the radio casing tobracket 42.

As is apparent, the radio in addition to being electrical- 1y connectedand fastened by the connectors to its brackets is suspended with fullprotection against shock and vibration because the suspension iseffected without direct metallic connection between the radio casing andthe 6 brackets which in turn are connected to or form part of the bodyof the car.

Figs. 6 and 7 show a connector which uses the principle and also some ofthe components of the connector described in connection with Figs. 1 and2, but makes use of the mechanical functions of the connector only. Thecam member and the elastic sleeve 7 are the same as in Figs. 1 and 2 anddesignated by the same reference numerals. The stud of the connector isshown as comprising a stem 61 secured on an end in or integral with arounded head 60 and having on the other end a longitudinal knurling 62.The knurled stem end serves to receive with a force fit a cam followermember 63 from which depend two noses 64 which coact with the cammingsurfaces of cam member 6. As is apparent, noses 64 correspond infunction to noses 11 of stud 5.

The connector of Figs. 6 and 7 is assembled by fitting stem 61 throughthe holes in a panel 50 and in a second panel 52 to be joined. Sleeve 7and cam 6 are thereupon slipped upon the protruding portion of stem 61.Finally, member 63 is force fitted upon knurling 62 so that its noses 64engage the camming surfaces of cam 6. The axial length of sleeve 7 isagain so selected that it is preloaded and hence slightly bulging whennoses 64 occupy the base of the camming surfaces of cam member 6. Theconnector is locked by turning the stud relative to the cam member untilnoses 64 enter the indentations 15 and 16 at the upper end of thecamming surfaces. The preloading of sleeve 7 supplies the necessarystarting friction between the engaging surfaces of sleeve 7, cam member6 and plate 50 respectively.

Fig. 6 shows the connector in its assembled and locked position.

Fig. 8 shows a gun for conveniently assembling a connector of the kindshown in Figs. 1 and 2, except that the Wing nut 9 is replaced byrounded head 51. The gun comprises a U-shaped bracket 55 from whichextends an upper support 56 and a lower support 57 between which theseveral components of the connector are assembled on support panel 50.The lower support 57 serves as a duct for supplying a fluid underpressure such as compressed air to the face of stud 5. The pressurefluid may be supplied to the gun through a hose connection. The figureshows stud 5 with its knurled portion 12 outside or just entering head51. By suitably regulating the axial pressure applied to stud 5, thesame is forced into head 51 just sufficiently deep to assure therequired preloading of sleeve 7 when the connector is unlocked.

While the invention has been described in detail with respect to certainnow preferred examples and embodiments of the invention it will beunderstood by those skilled in the art after understanding theinvention, that various changes and modifications may be made withoutdeparting from the spirit and scope of the invention, and it isintended, therefore, to cover all such changes and modifications in theappended claims.

What is claimed as new and desired to be secured by Letters Patent is:

1. In a two-part electric connector for releasably connecting twocoaxial cables each having a core conductor and an outer conductorthrough an opening in a metal wall, one of the connector partscomprising a metal stud fittable through said wall opening, said studsupporting on one end an enlarged conductive head electrically insulatedfrom the stud and on the other end a lateral protrusion, a rigid cammember slidably and rotatably supported on said stud between the headand the protrusion, said cam member having a camming surface coactingwith said protrusion to eflect axial displacement of the cam between aposition of maximum distance and a position of minimum distance relativeto said head upon rotation of the stud relative to the cam member, avibration suppressing axially deformable sleeve supported on said studbetween the head and the cam member, and also fittable through the wallopening the axial length of said sleeve being such as to cause aninitial predetermined axial deformation of the sleeve preloading thesame when the stud with the cam member and the sleeve supported thereonare fitted through said wall opening and the cam member is in itsposition of maximum distance, said pre-loading of the sleeve eifecting africtional engagement between the 'cam member and the respective face ofthe sleeve sufiicient to permit rotation of the stud and the protrusionthereon relative to the camming surface for increasing said initialaxial deformation of the sleeve to a predetermined maximum axialdeformation which causes an outward expansion of the sleeve overhangingthe wall opening for effecting fastening and sealing of said connectorpart within said wall opening, the outside wall of said sleeve beingmetallized so as to be in metallic engagement with said head and saidmetal wall upon fitting the stud through the wall opening, said studhaving means for conductive attachment of the core conductor of one ofthe coaxial cables and said head having means for conductive attachmentof the outer conductor of said cable.

2. In a two-part electric connector for releasably connecting twoco-axial cables each having a core conductor and an outer conductorthrough an opening in a metal wall, one of the connector partscomprising a metal stud fittable in said wall opening, said studsupporting on one end an enlarged conductive head electrically insulatedfrom the stud and on the other end a lateral protrusion, a rigid cammember slidably and rotatably supported on said stud between the headand the protrusion, said cam member having a camming surface coactingwith said protrusion to cited axial displacement of the cam between aposition of maximum distance and a position of minimum distance relativeto said head upon rotation of the stud relative to the cam member, avibration suppressing axially deformable sleeve supported on said studbetween the head and the cam member, rotation of the stud and itsprotrusion relative to the camming surface effecting an axialcompression of the sleeve to cause a predetermined maximum outwardexpansion of the sleeve overhanging the wall opening for fastening andsealing said connector part within said wall opening, the outside wallof said sleeve being metallized so as to be in metallic engagement withsaid head and said metal wall upon fitting the stud through the wallopening, said stud having means for conductive attachment of the coreconductor of one of the co-axial cables and said head having means forconductive attachment of the outer conductor of the said cable; and theother connector part comprising an inner contact element engageable withsaid stud and an outer contact element engageable with said metallizedsleeve wall, said inner contact element having means for conductiveattachment of the core conductor of the other coaxial cable and saidouter contact element having means for conductive attachment of theouter conductor of the latter cable.

3. An electric connector according to claim 2, wherein said outercontact element of the other connector part is a springy sleeve disposedin coaxial relationship with the inner contact element.

4. An electric conductor according to claim 3, wherein said stud ishollow and said inner contact element terminates in a contact pininsertable in said hollow stud, and wherein said springy sleeve isfrictionally engageable with the metallized outside wall of said sleeve.

5. An electric connector according to claim 1, wherein said sleeve has acollar abutting against said head and overhanging the peripheral outlineof said wall opening to form an area of frictional engagement betweenthe collar and the wall when the stud is fitted in said wall opening,the outside wall of the collar part abutting against said head beingalso metallized.

References Cited in the file of this patent UNITED STATES PATENTS2,167,286 Theobald July 25, 1939 2,513,305 Gagnier et al July 4, 19502,548,457 Wilson Apr. 10, 1951 2,688,894 Modrey Sept. 14, 1954

